$ git clone -n https://src.fedoraproject.org/rpms/beust-jcommander.git /var/lib/mock/f42-build-3408544-45145/root/chroot_tmpdir/scmroot/beust-jcommander
Cloning into '/var/lib/mock/f42-build-3408544-45145/root/chroot_tmpdir/scmroot/beust-jcommander'...
$ git fetch origin 8abf2093ef8e56a790b7e3ae403338496659ac9c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/beust-jcommander
 * [new ref]         8abf2093ef8e56a790b7e3ae403338496659ac9c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8abf209 Remove javadoc subpackage